I’m sure many of you already suspected this, but new research proves favoritism is rampant when it comes to employee promotions.

A survey recently released by Georgetown University’s McDonough School of Business that polled senior executives at large U.S. corporations found:

92 percent have seen favoritism at play in employee promotions.

84 percent have seen it at their own companies.

23 percent said they practiced favoritism themselves.

29 percent said their most recent promotion considered only a single candidate.

56 percent said when more than one candidate was considered, they already knew who they wanted to promote before deliberations.

96 percent report promoting the pre-selected individual.

“This survey reminds us that favoritism remains alive and well in the executive suite. Many playing fields still aren’t level,” said Lamar Reinsch, a professor of management at Georgetown’s McDonough School of Business.

And the study’s author, Jonathan Gardner, added that it’s critical to admit favoritism exists in order to find ways to mitigate the practice, which can lead to bad decision-making.

“It exists. Everyone knows it, but no one talks about it. It should be acknowledged,” he said.

“It’s an extension of what people just naturally do with one another,” said Simon Rego, director of psychology training at Montefiore Medical Center.

“We are all social beings and people respond to those connections,” he continued. “People want to promote those who they’d want to spend more time with.”

The issue of favoritism may be even more pronounced now, Rego surmised. In tough economic times many managers are worried about making the wrong decision and often go with known entities as a result.

“There are economic consequences for hiring or promoting someone and realizing it was a mistake,” he added.

So what does this mean for employees trying to climb the company ladder? Is it time to start kissing up? Maybe.

“On the one hand, the term ‘kissing up’ has very negative connotations,” explained Ronald Humphrey, a professor of management at Virginia Commonwealth University and author of forthcoming book “Modern Leadership: Traditional Theories and New Approaches.”

“On the other hand, a lot of people are afraid to compliment the boss because they don’t want to be seen as sucking up,” he added. But a good manager who does a good job and sticks up for employees may deserve some kudos, Humphrey maintained.

“Just saying thanks to a boss and establishing a good relationship is the right thing to do,” he said.

While job performance is the most important factor, Humphrey continued, if you sit alone at your desk and don’t interact with coworkers and managers, don’t expect to move up.

“An important part of leadership is solving complex tasks, but the ability to establish positive rapport with others is a good measure of your ability to be effective,” he stressed, acknowledging that favoritism is often unfair.

“There are some cases of someone being promoted for telling jokes to the boss rather than working hard,” he said. “We should promote on merit, but that doesn’t mean we shouldn't get to know our employees and care about them.”

Just because favoritism is rampant, however, doesn’t mean you should totally change your approach at work.

“I hope that people don’t overreact to some of the results,” warned Georgetown University’s Reinsch. “This research shows that most managers — most of the time — pay attention to past job performance and other relevant factors. It would be a mistake for an employee to seek a promotion through ‘apple polishing’ rather than performance.”

However, he added, “the results remind us that bosses are human beings who sometimes allow their judgment to be influenced by personal factors. So I would recommend that — in addition to doing your job well — an individual also try to remain on good terms with the boss. Being liked by the boss is a plus. But it isn’t — most of the time — a substitute for competence.”